The Cosmic Connection

From earliest times, human beings have pondered their place in the universe. They have wondered whether they are in some sense connected with the awesome and immense cosmos in which the Earth is imbedded. Many thousands of years ago a pseudoscience called astrology was invented. The positions of the planets at the birth of a child were supposed to play a major role in determining his or her future. The planets, moving points of light, were thought, in some mysterious sense, to be gods. In his...

Part Two The Solar System

There was a time - and very recently - when the idea of the possibility of learning the composition of the celestial bodies was considered senseless even by prominent scientists and thinkers. That time has now passed. The idea of the possibility of a closer, direct study of the universe will today, I believe, appear still wilder. To step out onto the soil of asteroids, to lift with your hand a stone on the moon, to set up moving stations in ethereal space, and establish living rings around the...

The Moons of Barsoom

In my boyhood I was lucky enough to come upon a set of turgidly written novels with names like Thuvia, Maid of Mars, The Chessman of Mars, The Princess of Mars, The Warlords of Mars, and so on. They were, needless to say, about Mars. But they were not about our Mars - the Mars revealed by Mariner 9. At least I don't think our Mars is like the Mars of these novels by Edgar Rice Burroughs, the inventor of Tarzan. His Mars was Percival Lowell's Mars - a planet of ancient sea bottoms, working...

The Unicorn of Cetus

In the night sky, when the air is clear, there is a cosmic Rorschach test awaiting us. Thousands of stars, bright and faint, near and far, in a glittering variety of colors, are peppered across the canopy of night. The eye, irritated by randomness, seeking order, tends to organize into patterns these separate and distinct points of light. Our ancestors of thousands of years ago, who spent almost all their time out of doors in a pollution-free atmosphere, studied these patterns carefully. A rich...

Civilizations

To deal with the possibility of enormously advanced extraterrestrial civilizations, the Soviet astrophysicist N. S. Kardashev has proposed a distinction in terms of the energy available to a civilization for communications purposes. A Type I civilization is able to muster for communications purposes the equivalent of the entire present power output of the planet Earth - which is now used for heating, electricity, transportation, and so on a large variety of purposes other than communication...

The Venus Detective Story

One of the reasons that planetary astronomy is such a delight these days is that it is possible to find out what's really right. In the old days, you could make any guess you liked, however improbable, about a planetary environment, and there was little chance that anyone could ever prove you wrong. Today, spacecraft hang like swords of Damocles over each hypothesis spun by planetary theoreticians, and the theoreticians can be observed in a curious amalgam of hope and fear as each new burst of...

Passage to Elsewhen

One of the most pervasive and entrancing ideas of science fiction is time travel. In The Time Machine, the classic story by H. G. Wells, and in most subsequent renditions, there is a small machine, constructed usually by a solitary scientist in a remote laboratory. One dials the year of interest, steps into the machine, presses a button, and presto, here's the past or the future. Among the common devices in time-travel stories are the logical paradoxes that accompany meeting yourself several...

Has the Earth Been Visited

By far the cheapest way of communicating with the Earth, if you're a representative of an advanced extraterrestrial civilization, is by radio. A single bit of radio information, sent winging across space to the Earth, would cost far less than a penny. A radio search for extraterrestrial intelligence seems, therefore, a very reasonable place for us to begin. But should we not examine other possibilities closer to home Wouldn't we look silly if we expended a major effort listening for radio...